べんけいかにじゃなかったです
弁慶蟹じゃなかったです
benkeikanijanakattadesu

Noun
Desu Copula

The polite, past negative form of べんけいがに

1. It wasn't Benkei crab.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana